The present invention is directed to a method and a process for surface treatment and, in particular, for sandblasting a large surface which is uneven.
The blasting is made with sand or a combination of sand and water for the elimination of rust, chipped paint, welding residue and the like. The treatment system is particularly adapted for projecting the sand or other material in a plurality of angular directions relative to the plane of the surface to be treated so that even the surface which has an intricate relief configuration can be handled satisfactorily.
The present system is also contemplated for projecting cleaning liquid, oil or powdered material.
The novel system is particularly adapted for the treatment of large surfaces such as truck boxes for vans or small platforms for trailors. The side and the doors of such surfaces display a large variety of reliefs.
In order to provide an adequate surface treatment for surfaces having such characteristics, the material being propelled must selectively move in or away from the surface to be treated. The nozzle of the spraying gun must angularly move according to a vertical and a horizontal axis so as to follow the exact shape of the surface to be treated including concealed corners.
Furthermore, considering that the system is contemplated for treating different types of surfaces, its manipulation must be simple and the projected material quickly displaced.